UKC

I've got a Wild country Mistral tent and the seam tape was perished to point where it is dry, stiff and flaking everywhere. 

How difficult is it to retape tent seams and do I need to get all the old flaky tape off completely or can I just do most and then tape over? Also should I reproof tent before or after re doing seams. 

It gets used infrequently now but is still a good tent

Thanks for any advice

My old 3 layer goretex was pretty easy to repair with iron on tape. What little residue there was of the old glue appeared to re-melt and certainly didn't limit adhesion.

Different fabric though so I guess it depends upon what type of tape you need.

Do you need to re-tape? I'd just cover the seams with sealant.

To be honest I hadn't thought of that as an option

I bought a tent that wasn't seam taped and the manufacturer's instruction was just to put sealant over the seams. Works fine and much easier to do.

Definitely just use seam sealant on the seams. It will probably be about an hour's work and take 8-10 hours to dry so make sure you pick a nice sunny day. Youtube has loads of tutorials of how to do it. 

Just used a seam sealer to sort my Terra Nova with exactly the issue you descibe and the results are spot on. Seamgrip do a silicone based tube for sil-nylon tents and another one for the other materials. Make sure you get the right one before sealing up. A single tube did my Quasar just fine.

Seam sealant appears to be the way to go. Thanks everyone

I took as much of the old tape off (as easily possible), then seam seal over.

That depends on the way the seams are sewn. Before seams were taped (more than 30 years ago) they were folded over and double stitched, silnylon tents still are. This is a very strong seam and only needs sealant to waterproof it.

Once taping became the norm, manufacturers saved money on seams by doing a simple running seam which is quite weak and used tape to both waterproof it and reinforce it.

If your tape has come off you will probably be left with a weak single row of stitching. Seam sealant won't add any strength to the seam and when the fabric is under tension the stitching will gape and leak anyway.

DIY iron on seam tape is a faff and not very good, spinnaker ripstop nylon self adhesive tape is much easier to use (google it) and does a good job though you should get the worst of the flaking stuff off first. It's 50mm wide though so you can cut it along the middle to make it 25mm and double its length.